(S)-2-(((S)-6,8-difluoro-1,2,3,4-tetrahydronaphthalen-2-yl)amino)-N-(1-(2-methyl-1-(neopentylamino) propan-2-yl)-1H-imidazol-4-yl)pentanamide (“Compound 1”) is a gamma-secretase inhibitor which can inhibit Aβ-peptide production.
Not all compounds that are gamma-secretase inhibitors have characteristics affording the best potential to become useful therapeutics. Some of these characteristics include high affinity at the gamma-secretase, duration of gamma-secretase deactivation, oral bioavailability, tissue distribution, and stability (e.g., ability to formulate or crystallize, shelf life). Favorable characteristics can lead to improved safety, tolerability, efficacy, therapeutic index, patient compliance, cost efficiency, manufacturing ease, etc.
In addition, the isolation and commercial-scale preparation of a solid state form of hydrobromide salts of Compound 1 and corresponding pharmaceutical formulations having acceptable solid state properties (including chemical stability, thermal stability, solubility, hygroscopicity, and/or particle size), compound manufacturability (including yield, impurity rejection during crystallization, filtration properties, drying properties, and milling properties), and formulation feasibility (including stability with respect to pressure or compression forces during tableting) present a number of challenges.
Accordingly, there is a current need for one or more solid state forms of hydrobromide salts of Compound 1 that have an acceptable balance of these properties and can be used in the preparation of pharmaceutically acceptable solid dosage forms.